The invention herein relates to an apparatus for forming thermal insulation blocks.
In the past it has been common to insulate high-temperature devices such as furnaces with fibrous insulations. Commonly used fibers have been glass fibers and refractory (usually aluminosilicate) fibers, which have commonly been in the form of batts or blankets. Such batts and blankets have been attached to the walls of the furnaces using impaling pins. The flexibility of such batts and blankets, and the fiber shrinkage which normally occurs at elevated temperatures, frequently causes gaps to open in the insulation, particularly at joints between adjacent insulation units. This, of course, significantly reduces the insulating value of the material.
Recently, modular thermal insulation has appeared commercially. Such insulation comprises blankets or batts of fibrous insulation folded into U-shapes and/or serpentine shapes and compacted into unitary blocks commonly measuring about 1 foot (30 cm) on a side and having a thickness of usually about 4-12 inches (10-30 cm). Such blocks are attached to a furnace wall in a parquet pattern, usually under compression, such that when shrinkage of the fiber occurs at the elevated temperatures in the furnace shrinkage occurring along the fiber direction of one block will be offset by the compression of the fibers in the adjacent modules. Typical of such blocks are those shown in U.S. Pat. Nos. 3,952,470 and 4,001,996, both issued in name of C. O. Byrd, Jr. Modular insulation of this type is available commercially under the trademark Z-BLOK from the Johns-Manville Corporation.
Initially such blocks were fabricated by hand. Such hand operations are of course undesirable, because they are slow and uneconomic. It would therefore be highly desirable to have apparatus which would not only fold the material into the desired shape and size for the block but also simultaneously insert into the folded material the supporting means by which the fibers are subsequently attached to mounting brackets and locked in place for subsequent mounting in a furnace or similar high temperature environment.